package cn.webrx;

import java.util.*;

public class HashMap4 {
    public static void main(String[] args) {
        HashMap<String,Student> map = new HashMap<>();
        map.put("20220101",new Student(1,"李四"));
        map.put("20220102",new Student(2,"张三"));
        map.put("20220103",new Student(3,"王五"));
        map.put("20220104",new Student(4,"赵六"));
        map.put("20220105",new Student(5,"李强"));
        map.put("20220106",new Student(5,"李强"));




        //Set<String> keys =  map.keySet(); //Set<String>
        //Iterator<String> it = keys.iterator();
        //it .hasNext() 返回boolean true
        //it.next()
        //while(it.hasNext()){
        //    System.out.println(it.next());
        //    System.out.println(it.next());
        //}





    }
}
